1. Field
Embodiments of the present invention relate to an organic light emitting diode display.
2. Description of the Related Art
An organic light emitting diode display includes two electrodes and an organic emission layer positioned therebetween, and electrons injected from one electrode and holes injected from the other electrode are coupled with each other in the organic emission layer to generate excitons, and the excitons emit energy to emit light.
Such an organic light emitting diode display includes a plurality of pixels, each of the pixels including an organic light emitting diode which is a self-emission device, a plurality of thin film transistors for driving the organic light emitting diode, and a storage capacitor. The plurality of thin film transistors basically includes a switching thin film transistor and a driving thin film transistor.
When light emitted by the organic light emitting diode is expressed or emitted from black to white according to a driving current Id flowing in the organic light emitting diode, a distance between a gate voltage corresponding to (e.g., expressing) black and a gate voltage corresponding to (e.g., expressing) white is defined as a driving range of the gate voltage. In the organic light emitting diode display, since a size of one pixel may be decreased as the resolution of the display increases, a current amount flowing per pixel may be decreased and thus the driving range of the gate voltage applied to the gate electrode of the driving thin film transistor is narrowed. Accordingly, it is difficult to control a magnitude of a gate voltage Vgs applied to the driving thin film transistor so as to have a sufficient number of rich grays.
The above information disclosed in this Background section is only for enhancement of understanding of the background of embodiments of the present invention and therefore it may contain information that does not form the prior art that is known to a person of ordinary skill in the art.